1. Field of the Invention
The invention relates in general to sealed electrical connectors, and in particular to a sealed connector assembly having an independently positionable TPA and interface seal.
2. Background Art
Sealed connectors, sometimes referred to as waterproof connectors, are commonly used to provide electrical connections in applications requiring a high degree of water resistance, such as in automobile wiring harnesses, appliances, underwater cameras, and other consumer devices. Waterproof connectors typically house one or more terminals secured to one or more terminal wire ends. A waterproof connector may be a male connector or a female connector, although female waterproof connectors are more common. The following descriptions will use female waterproof connectors as examples. However, one of ordinary skill in the art would appreciate that embodiments of the invention are equally applicable to male waterproof connectors.
Safety regulations currently require the use of a “TPA” (terminal position assurance) to assure proper positioning of the terminals within a connector housing. TPAs are used in both sealed and unsealed applications. The TPA locks the terminals in place in the process. Particularly in waterproof connectors, TPAs are frequently designed to also position and secure an interface seal that prevents intrusion of water into the housing. By convention, the end of a female connector that mates with a male connector may be referred to as the “front” end, and the opposite end through which a plurality of wires pass may be referred to as the rear end. Female waterproof connectors typically include “front loaded” interface seals for sealing at least a portion of the housing, as well as front-loaded, dual-function components that function both as a TPA and to energize or at least secure the interface seal. A wire seal, whose function includes preventing intrusion of water where the wires enter the housing, is typically loaded at the rear end, opposite the direction of the interface seal.
U.S. Pat. No. 6,190,203, for example, discloses a front-loaded “waterproof connector” comprising an outer housing, wherein a packing (interface seal) is inserted from the front and a spacer is then inserted from the front to hold the packing. A wire seal is positioned from the rear end of the housing. U.S. Pat. No. 5,931,699 similarly discloses a “waterproof connector,” wherein the interface seal is positioned and secured by another component from the front, and the wire seal is positioned from the back.
Some conventional connectors may use a dual-function TPA and seal retainer. These designs, however, may not guarantee proper positioning of the seals until the TPA is inserted to its final position. The TPA is typically fully assembled and positioned downstream in the connector supply and manufacturing chain. TPAs typically have a pre-set position that they are shipped in, and the TPA is inserted into its final position only after all of the female terminals are inserted. The seals risk being improperly positioned or even dislodged in the interim. After the female terminals and TPA are assembled, the female connector is then inserted into the male connector. Furthermore, engagement and disengagement of the TPA with respect to the connector housing, as well as engagement and disengagement of the female connector with respect to the male connector, may each create a pressure change within the housing that can dislodge the interface seal and/or the wire seal.
Conventional connectors having such designs limit the direction of assembly of at least the interface seal. The interface seal must be inserted from the front, such that the TPA may subsequently engage that seal. The wire seal, however, is typically assembled from the rear, and the two seals are therefore assembled from opposite directions, which complicates the manufacturing and assembly process.
Furthermore, conventional connectors may not work on some applications subject to significant size constraints. Downstream manufacturers and suppliers who purchase connectors for further use or assembly typically stipulate size constraints for connector parts and packaging. Dual-function TPA and seal-retaining components impose design limitations, wherein the size of the connector may not be optimized to conform to more stringent sizing requirements.
Regulations governing connector manufacturing, assembly, and installation are subject to change. The seal-retaining feature and the TPA feature in a dual function piece are unnecessarily tied to the same component or set of components. Changes in TPA requirements that dictate modification or elimination of the TPA may undesirably impact design of the seal-retaining feature.
Therefore, there exists a need for better designs of waterproof connectors.